The near-vacuum extending between the planets and stars, containing small amounts of gas and dust. Also called outer space to refer to the physical universe beyond the Earth's atmosphere.

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Is dark energy around a black hole locally curved?

The repartition of dark energy in the vacuum is homogeneous all over the universe. The diagram below represents space with a black hole in the middle. The square is divided in small unit squares. If ...
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1answer
60 views

Is what i think Magnetism is, Magnetism? [closed]

So, i was randomly thinking about magnets one day and decided to try and figure out what Magnetism actually is. This is what i came up with: Magnetism, the magnetic field of an object, is a form of ...
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2answers
93 views

Gravity: Is there curved space besides curved spacetime?

Wikipedia: Curved spaces play an essential role in General Relativity where gravity is often visualized as curved space. Is the Wikipedia article "curved space" talking about curved space or ...
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1answer
31 views

Can invisible galaxies exist? [duplicate]

Is it possible that there are newly formed galaxies which are moving so fast that we will can't see them, even though they exist "inside" our visible universe? I've been wondering if this could be a ...
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2answers
494 views

Why superconductors aren't used in space?

As we all know temperature of space is near to absolute zero.Then why super conductors aren't used there?
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3answers
71 views

How strong must gravity be to stretch time?

I'm not sure if this is true or not but I heard that gravity has the ability to stretch time, and I was wandering if this is true. If so, how intense/powerful does the gravitational force have to be ...
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1answer
49 views

Empty Space - Could we exist without it? [closed]

I have been giving empty space much thought. I imagined reaching the edge of the Universe and thought of 2 scenarios(focusing on 1): There is no more empty space 1.1 Would space extend with me if ...
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1answer
51 views

Why are heat-shields on re-entry vehicles smooth and not textured to increase drag?

Meteorites naturally texture themselves via the formation of regmaglypts, 'thumbprint-shaped' indentations caused by ablation of their surface, during entry into the atmosphere. This appears to ...
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2answers
2k views

Heat Transfer From a Spaceship in Deep Space

Space is a very low temperature environment, however it also has an extremely small number of particles per unit volume. This leads me to believe that, contrary to popular portrayals of heat loss in ...
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3answers
1k views

Can black holes actually merge?

If time stops at the event horizon, can we ever detect two black holes merging? In other words, if you are a short distance away, would you encounter a spherically symmetric gravitational field, or a ...
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3answers
91 views

Can asteroids fall on earth and hit the surface at 90 degree angle?

I always Saw in movies ,cartoons every where that asteroids hit the earth at an angle (not 90 degree). But Why ? ...
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3answers
1k views

Would a thinner atmosphere (such as high altitude) yield better solar panel energy generation?

I am curious. If you were to put a solar panel up in high altitude or on the surface of the moon, both of which have much less atmosphere to reflect/refract light, would that solar panel produce more ...
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5answers
217 views

Can “vacuum be brought” from outer space?

Instead of creating vacuum in chambers on earth, why can't vacuum be brought from outer space in chambers? Outer space pressure ranges from $10^{-6}$torr to $10^{-17}$torr very very low. Is it ...
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2answers
152 views

Could a really tall tube suck garbage in to space?

When I was around 10 years old, I had this idea that was supposed to solve our waste problems; I imagined having tubes miles high that would stretch in to space. Every tube would have a door at the ...
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2answers
454 views

How electromagnetic fields travel through vacuum?

How electromagnetic fields travel through vacuum is it right to say that they propagate or travel? do they alternately form each other by charged particles?
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3answers
2k views

How does blood/saliva boil in outer space?

Why would the blood boil? Is it because of the temperature or pressure? Because I really can't figure it out. I thought space didn't have a temperature above freezing unless close to a star or the ...
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1answer
57 views

How many times does the ISS celebrate New Year each year? [closed]

My question is, how many times each year do the crew of the ISS have an opportunity to celebrate New Year? Does it vary each year or will it be a fixed number? I tried to work this out for myself ...
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2answers
144 views

How, exactly, does a reaction wheel work?

Reaction wheels, mounted on spacecrafts and satellites, are used for precision attitude control. It is not clear to me how they can do this, though. My best guess is that when a motor accelerates a ...
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3answers
711 views

Does the Earth actually rotate around the sun? [duplicate]

Why does one say that the Earth rotates around the sun? There should be no preferred reference frame and from an observer on the sun, the sun will rotate around the Earth.
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4answers
62 views

What happens when I place an object of certain temperature in space ? Does it loose its entire heat energy?

Can i obtain absolute zero temperature this way? And let's assume there is no cosmic microwave background and also assume that there is a way to shield the object from any heat source, such as the ...
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1answer
82 views

If I take a bottle of air into space, and open it, then close it and come back to earth and open it one last time, what would happen?

I was reading this post, but no one seem to go further as say what would happen if you brought the bottle back to Earth? Guess what another thing I'm wanting got know is, what would now be in the ...
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1answer
268 views

What makes a space a real space?

By "real space" I mean a space in which physical particles move. Consider a color sphere and let a bunch of objects "move" on its surface. "Move" means "change colors". Let there be some rules ...
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4answers
14k views

If there is no gravity on the moon why is the american flag waving?

If there is no gravity on the moon, how could this flag be flapping in the wind? (see link) http://www.stumbleupon.com/su/2wD6eg/hea-www.harvard.edu/~fine/images/desktops/Armstrong.jpg
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0answers
26 views

Are the Van Allen belts important to life? [closed]

Is it significant for life on Earth? Mars doesn't have this. Why do experts think there may be life on it? What kind of life form could live on Mars? This article I just read got me wondering. A ...
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2answers
382 views

What exactly is the composition of radiation in interplanetary space?

The articles I found on radiation in the solar system mostly dealt with solar wind, I wonder about other types. Is there a breakdown that tells me, withhin an order of magnitude, at least what ...
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1answer
40 views

How did the Huygens probe use EM waves to measure wind speeds on Titan?

In the Wikipedia's article on Huygens spacecraft, it was mentioned that one of the experiments was to measure the wind speeds on Titan by Doppler wind experiment. To quote the exact lines, it was ...
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15 views

Kármán Line Definition from “Aeronautical Flight” (Mass, Area, and Lift)

This question asks something very similar, and the single following answer says, in part, that the balance is achieved when: $$ \frac{2m}{\rho(r) A C_L r} = 1 $$ [...] I note that the mass ...
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1answer
51 views

Maneuvering a space shuttle using propulsion systems?

A colleague and I randomly started on this subject, and, not being very good at anything science / physics related we were stumped at how this might work. So the question is: If I park my space ship ...
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3answers
78 views

Would the rotation of a space ship in vacuum slow it down

Firstly , a few disclaimers : English is not my native language so I may use the wrong technical terms. Please notify me and I will correct the question. As a CS major , I've only taken one class ...
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1answer
62 views

What does it mean to say that “6 tons of dark energy would be found within the radius of Pluto's orbit”?

What does it mean to say that "6 tons of dark energy would be found within the radius of Pluto's orbit"? Does it mean that the dark energy is orbiting the solar system? Or does it mean a flow of ...
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1answer
72 views

What will I see if I travelled to a distant planet in 100 times faster than speed of light and look back? [closed]

Consider this scenario. I enter a space ship at 10:00 AM, it starts to move at a speed 100 times faster than light, I travel for 55 mins. And then slow down to very much less than speed of light and ...
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0answers
70 views

What is the true fundamental 'stuff' of physics? [closed]

It seems to me that most if not all of the publications and the institutional education of physics 'jump in' and start describing detailed phenomena without spending too much time describing and ...
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4answers
2k views

Will a stone thrown in space move forever?

If I throw a stone on space, in a place where gravity is equal zero, will the stone move forward forever, because no air, so no friction?
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1answer
66 views

Help understanding centre of mass

So basically the question I posed myself a few days ago was for a torus shaped planet, what would the gravitational field be like inside the torus? After viewing some answers on the internet, (Gravity ...
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6answers
873 views

The earth is spinning, so why don't we jump and land on a different location?

I know there are similar questions in stackexchange but i think it's different and detailed. The earth is spinning 465 meters/second so why don't we jump and land on a different location ? I have ...
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3answers
353 views

Why were space physicists wrong about the location of the heliopause?

The heliopause is now estimated to be something around 100 AU (1 AU = Astronomical unit = about the earth sun distance). See the wikipedia article: http://en.wikipedia.org/wiki/Heliosphere From ...
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0answers
32 views

How different sizes of water bubbles behaves in space

I watched a YouTube video of Chris Hadfield talking about different preventive measure for spills in space station. He is using water to demonstrate spills in space station. At 0.24sec the initially ...
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3answers
213 views

Why aren't stratospheric balloons compressing their helium to descent? [closed]

I can't find a reference of a working stratospheric balloon mounted with a compressor to control its altitude. Is there a big physical difficulty (such as compressor weight/power ratio, or power ...
2
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1answer
51 views

“Voyager: Lightning on Jupiter”: what's a sound source for this?

NASA created an official Soundcloud channel with a various sounds from missions. There are a Voyager: Lightning on Jupiter sound. Is there are ay information on how's this sound is produced (and ...
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2answers
1k views

Elasticity of Space; How does the expansion of Space affect gravity?

Does space have an elastic quality? What I was thinking about was if space is expanding, is it being 'stretched', like a balloon being blown up, and if so, is this causing gravity to weaken? Imagine ...
2
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1answer
71 views

Is there, and if there is, what is the name of the concept that matter is made out of void/space?

I can't recall where I heard about this, but it was rather intriguing. I recall the notion that matter is compressed void/space, where I remember an example of a bedsheet representing space, and the ...
1
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1answer
31 views

How to calculate heat generated from cosmic dust in space? [duplicate]

Say I have a spaceship, and I'm flying it through space at a constant high velocity V. The spaceship is pretty large (big surface area). In space however, there is cosmic dust scattered throughout ...
2
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3answers
87 views

Is the amount of radiation you receive in space constant regardless of velocity?

I'm only in high school, so this will probably have fatal flaws. So basically in space, there is bound to be stray radiation, whether from the stars, or cosmic background, floating around right. And ...
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1answer
79 views

Calculating change in gravitational potential energy [closed]

A satellite mass $500\ kg$ is elevated from altitude $10000\ km$ to altitude $20000\ km$. Radius of earth is $6378\ km$. Mass of earth is $5.97 \cdot 10^{24}\ kg$. Gravity is given to be $9.81\ m/s $ ...
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3answers
7k views

What is meant by Vacuum?

What is the exact meaning of the word vacuum? Is it just a state of very low pressure or is it nothingness (as in there is nothing)? Also, when we say space is vacuum - it must be referring to ...
5
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1answer
128 views

How fast until you feel wind in space? [duplicate]

I couldn't find this question asked anywhere else, so I thought I would ask it here: does anyone know how fast you would have to be traveling in space to feel 'wind' from the particles in front of ...
2
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1answer
57 views

What's wrong with this temperature-in-space calculation?

I'm trying to calculate the steady-state temperature of a body in space, but my numbers are coming up much too small. For example, for a 1-meter cube, I'm getting a temperature of 194 K (or -81 C). ...
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1answer
134 views

What exactly happens to an exposed human body in space?

I know that space is a vacuum, has no air and is very, very cold. from what i have seen in movies and TV shows when a space suit is exposed the oxygen will escape will escape like a visible gas and ...
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15answers
3k views

What are the mechanics by which Time Dilation and Length Contraction occur?

What are the mechanics of time dilation and length contraction? Going beyond the mathematical equations involving light and the "speed limit of the universe", what is observed is merely a phenomenon ...
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4answers
199 views

Gravity doesn't seem to work the way it is supposed to [duplicate]

This has been a bit of an awkward question that's been plaguing me ever since I started watching space documentaries on discovery about 10 years ago. I was saving this for the day I would ever meet ...